|Publication number||US4649280 A|
|Application number||US 06/732,773|
|Publication date||Mar 10, 1987|
|Filing date||May 10, 1985|
|Priority date||May 10, 1985|
|Publication number||06732773, 732773, US 4649280 A, US 4649280A, US-A-4649280, US4649280 A, US4649280A|
|Inventors||William R. Holland, Dennis G. Hall|
|Original Assignee||The University Of Rochester|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (3), Non-Patent Citations (6), Referenced by (83), Classifications (7), Legal Events (4)|
|External Links: USPTO, USPTO Assignment, Espacenet|
The present invention relates to methods and systems for the enhancement of fluorescence, and particularly to fluorometric systems and methods whereby the presence, concentration or absence of substances may be determined.
The invention is especially suitable for use in fluorescent assay methods and apparatus wherein substances to be assayed are coated onto a substrate in fluorescent form. The fluorescence is detected to provide a signal from which the presence and nature of the substance may be determined. Reference may be had to U.S. Pat. No. 3,992,631 issued Nov. 16, 1976, further information respecting fluorescent assay methods and apparatus of the types which have heretofore been proposed.
It is desirable in fluorescent assay techniques that the intensity of the fluorescence be significant so as to enable the detection thereof by photodetectors to provide electrical signals much larger than the noise. Otherwise the presence and concentration of the substances of interest cannot be quantitatively determined with acceptable accuracy.
In conventional fluorescent assay systems the material to be assayed is labeled with fluorescent material and coated on a glass slide. The coated slide is then exposed to excitation light and the emitted fluorescence is photodetected to obtain the signal which is analyzed. Utilizing the method and system provided by the invention can give rise to an enhancement factor over the conventional system in excess of two orders of magnitude (over 100 times enhancement).
Enhancement of fluorescence has been reported utilizing layers of fluorescent material deposited on silver island films. See A.M. Glass et al., Optics Letters, Vol. 5, No. 9, pp. 368-370 (September 1980). An enhancement of the fluorescence of about one order of magnitude is reported by Glass et al. Glass et al. and other investigators have ascribed the enhancement to molecule-surface interaction processes. See A.M. Glass et al., Phys. Rev. B 24, 4906 (1981); A. Wokaun et al., Phys. Rev. B 24, 849 (1981); D. A. Weitz et al., Opt. Lett. 7, 89 (1982); D.A. Weitz et al., J. Chem. Phys. 78(9), 5324 (1983); W. R. Holland, Phys. Rev. B 27(12) 7765 (1983); and W. R. Holland et al., Phys. Rev. Lett. 52(12), 1041 (1984).
In accordance with the present invention, the modes of an optical waveguide are used to generate a strong field in the vinicity of a film of fluorescent material, and particularly from the layer of molecules of the material which defines a wall of the optical waveguide. The remainder of the waveguide is defined by a layer of dielectric material having a film of conductive (preferably also reflective) material on the surface of the dielectric layer opposite that on which the layer of fluorescent molecules is disposed. The excitation radiation which is incident on the fluorescent material is self-coupled to the waveguide to support the propagation of the modes which generate the strong field. No external means such as prisms or gratings are required to couple the incident excitation into the modes of the optical waveguide. The system is simple in configuration and provides fluorescence that is enhanced in the range of two orders of magnitude over that from the same quantity of fluorescent material deposited on a glass substrate (typically a microscope slide), as would be the case if conventional fluorescent assay techniques were followed.
The fluorescence enhancement is believed to be attributable to the coupling between the molecules of the fluorescent material and the propagating modes of the system. The operation of the waveguide mode enhancement of molecular fluorescence provided by the invention may be appreciated better by analogy to an antenna having an emitting dipole closely coupled to a directive structure which has gain at the wavelengths over which coupling occurs. The molecular overlayer provided by the molecules of fluorescent material is critical to the enhancement and gain from the system. In the absence of the molecular overlayer, a plane-wave incident on a substrate from air has a parallel (to the surface of the substrate) wave-vector component that is too small to permit excitation of guided modes in a waveguide structure. Because the near-field of a molecule contains a large distribution of parallel (to the surface) wave-vector component values, the presence of the layer of molecules in the waveguide structure effects the coupling between the incident, fluorescent exciting light and the waveguide modes because of the spatial overlap between the dipole field from the molecule and the modal fields in the waveguide structure. The net effect of the coupling is an enhanced molecular absorption rate due to the large local (to each molecule) fields produced by the modes at the wavelength of the incident light, and an enhanced radiative effect due to the coupling with the modes at the emission wavelength (the wavelength of the fluorescence). It should be understood that the foregoing theoretical discussion and the analogy to an antenna is theoretical and is given in order to facilitate an understanding of the invention and is not intended to limit the invention to any mode of operation, theoretical or otherwise.
Accordingly, the principal object of the invention is to provide an improved method and system for the enhancement of fluorescence.
More specifically, it is an object of the present invention to provide an improved method and system for obtaining enhanced fluorescence from the molecules of fluorescent material deposited on and defining the surface of an optical waveguide structure.
It is a still further object of the present invention to provide improved methods and systems whereby fluorescent assays may be carried out.
The foregoing objects, features and advantages of the invention, as well as a presently preferred embodiment thereof, and the best mode now known for carrying out the invention, will become more apparent from a reading of the following description in connection with the accompanying drawings in which:
FIG. 1 is a schematic diagram of the crosssection of a system for enhancing fluorescence in accordance with the invention;
FIG. 2 is a schematic diagram illustrating the operation of the system and the method for enhancing the detection of fluorescence in accordance with the invention; and
FIG. 3 is a plot illustrating the enhanced fluorescence as a function of the thickness of the layer of dielectric material, d, in the structure illustrated in FIGS. 1 and 2 in terms of the ratio of the intensity of the fluorescence, IA from the system in accordance with the invention to IREF which is the intensity of the fluorescence from a reference sample wherein the fluorescent material is directly deposited on an uncoated glass slide.
Referring first to FIG. 1, there is shown, schematically, a diagram of a three layer structure which provides the fluorescence enhancement system in accordance with a presently preferred embodiment of the invention. A glass substrate 10, which may be a rectangular glass slide, is coated with a film 12 of conductive, reflective material. Vacuum deposition techniques of the type normally used in the fabrication of optical devices may be used. Preferably the film covers the entire slide and may have a thickness which enables the film 12 to be partially transparent, for example, partially transmissive of 20% of the light which is incident normal to the surface thereof. The thickness of this film 12 is suitably 50 nanometers (nm) when the film material is the metal Ag. Other metals may need other thicknesses.
A layer 14 of thickness, d, of a transparent dielectric material is deposited upon the conductive, reflective film 12 and extends over the entire area of the slide 10. Suitably, this layer is of Lithium Flouride (LiF), and other dielectrics are usable as well. This thickness, d, of the layer 14 is critical and depends upon the wavelength of the exciting, incident radiation and the emissions (fluorescence) wavelength, as will be apparent from FIG. 3. In an exemplary embodiment, the depositions of the film 12 and the layer 14 were made by thermoevaporation in a cryogenically pumped system at pressures in the 10-8 Torr range. Film thicknesses may be measured using a quartz-crystal film-thickness monitor.
A film of fluorescent material 16 is deposited over the dielectric layer 14. It is illustrated as the row of solid black spheres to schematically show the molecular layer at the interface 18 between the film of fluorescent material 16 and the layer of dielectric material 14. The fluorescent material may be organic material, such as Rhodamine B, or any other materials, the molecules (organic or inorganic) of which are labelled with a fluorescent component. The fluorescent component may be bound to the molecule of interest in accordance with techniques used in fluorescent assays. The thickness of the layer 16 is desirably of the order of single molecules in thickness. The thickness is not especially critical. It is important, however, that the layer 16 not be so thick that the incident, exciting light does not reach molecules which are close to the interface 18. The interface 18 and the interface 19 between the layer 14 and conductive film 12 are desirably in parallel planes.
By way of example, the fluorescent material layer 16 may be applied after the device coated with the conductive layer 12 and dielectric layer 14 is removed from the vacuum system. The device is immediately placed in a second vacuum system equipped with a resistively heated source containing solid organic material, for example, the organic dye Rhodamine B. Extremely slow heating of the dye (at a pressure of approximately 2 times 10-6 Torr) to a temperature near its melting point of approximately 275° C. causes the organic dye to vaporize to form a thin layer of dye on the interface 18. In this example the dye evaporation is stopped when the quartz-crystal film thickness monitor registers a thickness of 30 Angstroms, approximately. This is an approximation since it is based on the assumption that the dye has a density of one gram per cubic centimeter. Other techniques may be used to provide the film of fluorescent material 16, for example, by dipping to provide well-ordered layers in accordance with the Langmuir-Blodgett technique or by spin coating of the material in liquid form, suitably dissolved in a solvent, and placed on the interface 18.
The fluorescent material film 16, the dielectric layer 14 and the layer of reflective conductive material define an optical waveguide which supports a plurality of propagation modes including the TE0 and the TM1 modes.
The presence of these modes and the existence of waveguide propagation is demonstrated in the apparatus shown in FIG. 2 where the device 20 is similar to the device shown in FIG. 1 and has the fluorescent material film 16, the dielectric layer 14, the conductive layer 12 and the substrate 10. A prism 22 which is index-matched to the substrate 10 allows the projection of fluorescence indicated by the rays 24, 26 and 28 at angles, θ, to a photodiode detector. The rays 24, 26, and 28 designate light emitted by the waveguide modes at the fluorescence wavelength. The intensity of this radiation is shown as IP and is detected by a photodetector 30 which may suitably be a photomultiplier followed by a photon-counting electronics system. A slit and filter which blocks the excitation wavelength is suitably placed in the path of the rays 24 to 28 ahead of the photodetector 30.
The incident, exciting wavelength may be a light beam from an excitation source, suitably a laser, however, an incandescent light-source is usable. In the case of Rhodamine B the excitation wavelength may be from an Argon-Ion laser at a wavelength of 514.5 nm. The beam may be of low power (for example less than 1/10th milliwatt). The fluorescence wavelength is 540 nm. The incident beam is indicated as arriving at an angle of incidence, φ, and the intensity of the incident radiation is indicated as I0. The fluorescence is indicated by the ray 32 and its intensity is indicated as IA. A photodetector 34 detects the fluorescence. A monochrometer may be used to select the fluorescence wavelength. The photodetector may also be a photomultiplier followed by a photon-counting electronic system.
The enhancement is shown in FIG. 3. FIG. 3 is for the exemplary case where the excitation beam is at an angle of incidence, φ, of approximately 15° and the fluorescence is observed along the normal as shown in FIG. 2. The vertical axis of the plot of FIG. 3 is labeled in units of enhancement quantity, IA /IREF, where IREF is the fluorescence signal obtained from a similar dye layer deposited on an uncoated microscope slide.
The enhancement of the fluorescence is attributed to the coupling between the dye molecules at or close to the interface 18 and the propagating modes of the waveguide structure. It will be observed that the enhancement is in excess of two orders of magnitude where the dielectric layer is approximately 180 nanometers, for the Rhodamine B fluorescent material used in the above example. Of course the thickness d will depend upon the excitation and emission wavelengths and is selected as a compromise so that modes of propagation at both the incident and the emission wavelengths will be supported by the waveguide. The thickness of the conductive film 10 is not critical when measurements such as that of IP are not needed. The propagating modes of optical radiation are best supported when the conductive layer is substantially fully reflective of the exciting radiation and also of the fluorescence (the emitted radiation from the fluorescent material film 16). Other variations and modifications within the scope of the invention will undoubtedly suggest themselves to those skilled in the art. Accordingly, the foregoing description should be taken as illustrative and not in a limiting sense.
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US3992631 *||Feb 27, 1975||Nov 16, 1976||International Diagnostic Technology, Inc.||Fluorometric system, method and test article|
|US4262206 *||Jan 11, 1980||Apr 14, 1981||The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration||Fluorescent radiation converter|
|US4371897 *||Apr 27, 1981||Feb 1, 1983||Xerox Corporation||Fluorescent activated, spatially quantitative light detector|
|1||Drexhage, K. "Interaction of Height with . . . Dye Layers", Progress in Optics, Ed. E. Wolf, vol. XII, 1974, p. 191.|
|2||*||Drexhage, K. Interaction of Height with . . . Dye Layers , Progress in Optics, Ed. E. Wolf , vol. XII, 1974, p. 191.|
|3||Glass et al, "Interact. of Metal Particles with Absorb. Dye", Optics Letters, vol. 5, No. 9, Sep. 1980, p. 368.|
|4||*||Glass et al, Interact. of Metal Particles with Absorb. Dye , Optics Letters , vol. 5, No. 9, Sep. 1980, p. 368.|
|5||Holland et al, "Surface-Plasman Dispersion . . . ", Physical Review B, vol. 27, No. 12, Jun.-83, p. 7766.|
|6||*||Holland et al, Surface Plasman Dispersion . . . , Physical Review B, vol. 27, No. 12, Jun. 83, p. 7766.|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US5006716 *||Feb 22, 1989||Apr 9, 1991||Research Corporation Technologies, Inc.||Method and system for directional, enhanced fluorescence from molecular layers|
|US5023139 *||Oct 6, 1989||Jun 11, 1991||Research Corporation Technologies, Inc.||Nonlinear optical materials|
|US5162654 *||Feb 1, 1991||Nov 10, 1992||Wisconsin Alumni Research Foundation||Detection apparatus for electrophoretic gels|
|US5344784 *||Nov 28, 1989||Sep 6, 1994||Applied Research Systems Ars Holding N.V.||Fluorescent assay and sensor therefor|
|US5478755 *||Feb 17, 1994||Dec 26, 1995||Ares Serono Research & Development Ltd.||Long range surface plasma resonance immunoassay|
|US5552272 *||Jun 10, 1993||Sep 3, 1996||Biostar, Inc.||Detection of an analyte by fluorescence using a thin film optical device|
|US5776785 *||Dec 30, 1996||Jul 7, 1998||Diagnostic Products Corporation||Method and apparatus for immunoassay using fluorescent induced surface plasma emission|
|US5841143 *||Jul 11, 1997||Nov 24, 1998||The United States Of America As Represented By Administrator Of The National Aeronautics And Space Administration||Integrated fluorescene|
|US5891741 *||May 16, 1997||Apr 6, 1999||Coulter International Corp.||Antibody-aminodextran-phycobiliprotein conjugates|
|US6395483||Oct 1, 1999||May 28, 2002||3M Innovative Properties Company||Arrays with mask layers|
|US6492133||May 1, 2000||Dec 10, 2002||3M Innovative Properties Company||Reflective disc assay devices, systems and methods|
|US6593089||Jul 20, 2001||Jul 15, 2003||3M Innovative Properties Company||Arrays with mask layers and methods of manufacturing same|
|US6664060||Jul 20, 2001||Dec 16, 2003||3M Innovative Properties Company||Arrays with mask layers and methods of manufacturing same|
|US6740897 *||Dec 14, 2001||May 25, 2004||Fuji Photo Film Co., Ltd.||Radiation image storage panel and process for reading radiation image information|
|US6807323 *||Mar 4, 2002||Oct 19, 2004||Electronics And Telecommunications Research Institute||Active ion-doped waveguide-plasmon resonance sensor based on upconversion of active ions and imaging system using the same|
|US6893876 *||Dec 1, 2000||May 17, 2005||Commissariat A L'energie Atomique||Enhancing surface-generated fluorescence signal emitted by a sample|
|US6900028||Oct 10, 2002||May 31, 2005||3M Innovative Properties Company||Reflective disc assay devices, systems and methods|
|US6999222 *||Aug 13, 2003||Feb 14, 2006||The Regents Of The University Of California||Plasmon assisted enhancement of organic optoelectronic devices|
|US7154598||Jul 14, 2003||Dec 26, 2006||Decision Biomarkers, Inc.||Excitation and imaging of fluorescent arrays|
|US7158224||Jun 25, 2001||Jan 2, 2007||Affymetrix, Inc.||Optically active substrates|
|US7285789 *||Jun 3, 2004||Oct 23, 2007||Oc Oerlikon Balzers Ag||Optical device for surface-generated fluorescence|
|US7358079||Dec 13, 2000||Apr 15, 2008||Bayer Technology Services Gmbh||Flow cell array and the utilization thereof for multianalyte determination|
|US7400397 *||Jul 18, 2006||Jul 15, 2008||University Of Maryland, Baltimore||Optical structures for metal-enhanced sensing|
|US7492978 *||Oct 7, 2002||Feb 17, 2009||The Secretary Of State For Defence||Waveguide structure|
|US7678565||Feb 21, 2008||Mar 16, 2010||Bayer Technology Services Gmbh||Flow cell array and the utilization thereof for multianalyte determination|
|US7708945||Aug 3, 2000||May 4, 2010||Bayer Technology Services Gmbh||Device and method for determining multiple analytes|
|US7750316 *||May 10, 2006||Jul 6, 2010||Dublin City University||Polymer biochip for detecting fluorescence|
|US7767131||Aug 26, 2002||Aug 3, 2010||Bayer Technology Services Gmbh||Method for production of moulded bodies, in particular optical structures and use thereof|
|US7855785||Mar 2, 2006||Dec 21, 2010||Centre National De La Recherche Scientifique (Cnrs)||Fluorescence detection device|
|US7927868||Mar 17, 2010||Apr 19, 2011||Bayer Technology Services Gmbh||Device and method for determining multiple analytes|
|US8053225||Jan 28, 2010||Nov 8, 2011||Bayer Technology Services Gmbh||Flow cell array and the utilization thereof for multianalyte determination|
|US8247216||Sep 25, 2009||Aug 21, 2012||Pacific Biosciences Of California, Inc.||Ultra-high multiplex analytical systems and methods|
|US8335029||Mar 10, 2011||Dec 18, 2012||Pacific Biosciences Of California, Inc.||Micromirror arrays having self aligned features|
|US8380020||Jun 21, 2010||Feb 19, 2013||Weidmann Plastics Technology Ag||Planar optical structure forming an evanescent field measuring platform that includes a layer molded by a master|
|US8993307||Jul 18, 2012||Mar 31, 2015||Pacific Biosciences Of California, Inc.||High multiplex arrays and systems|
|US9109793||Jul 20, 2010||Aug 18, 2015||Crayola, Llc||Illuminated display unit|
|US20020171045 *||Dec 1, 2000||Nov 21, 2002||Francois Perraut||Enhancing surface-generated fluorescence signal emitted by a sample|
|US20020182631 *||Dec 13, 2000||Dec 5, 2002||Eveline Schurmann-Mader||Flow cell array and the utilization thereof for multianalyte determination|
|US20030040034 *||Oct 10, 2002||Feb 27, 2003||3M Innovative Properties Company||Reflective disc assay devices, systems and methods|
|US20030087297 *||Nov 4, 2002||May 8, 2003||Yokogawa Electric Corporation||Biochip and genetic sequence measuring equipment using the biochip|
|US20030099422 *||Mar 4, 2002||May 29, 2003||Beom Shin Yong||Active ion-doped waveguide-plasmon resonance sensor based on upconversion of active ions and imaging system using the same|
|US20030170447 *||Mar 10, 2003||Sep 11, 2003||Yokogawa Electric Corporation||Fluorescence-enhanced bead|
|US20030232427 *||Jun 17, 2003||Dec 18, 2003||Montagu Jean I.||Optically active substrates for examination of biological materials|
|US20040046128 *||Aug 28, 2003||Mar 11, 2004||Andreas Peter Abel||Sensor platform and method for the determination of multiple analytes|
|US20040125370 *||Jun 25, 2001||Jul 1, 2004||Montagu Jean I.||Optically active substrates|
|US20040149928 *||Feb 3, 2003||Aug 5, 2004||Gruhlke Russell W.||Tunable cross-coupling evanescent mode optical devices and methods of making the same|
|US20040197595 *||Aug 26, 2002||Oct 7, 2004||Tilo Callenbach||Method for production of moulded bodies, in particular optical structures and use thereof|
|US20050009198 *||Sep 11, 2002||Jan 13, 2005||Maccraith Brian||Luminescence-based sensor assembly|
|US20050017191 *||Jul 14, 2003||Jan 27, 2005||Montagu Jean I.||Excitation and imaging of fluorescent arrays|
|US20050019836 *||Dec 4, 2001||Jan 27, 2005||Horst Vogel||Bioanalytical reagent, method for production thereof, sensor platforms and detection methods based on use of said bioanalytical reagent|
|US20050035346 *||Aug 13, 2003||Feb 17, 2005||Bazan Guillermo C.||Plasmon assisted enhancement of organic optoelectronic devices|
|US20050051733 *||Jun 3, 2004||Mar 10, 2005||Unaxis Balzers Ltd.||Optical device for surface-generated fluorescence|
|US20050053974 *||May 20, 2004||Mar 10, 2005||University Of Maryland||Apparatus and methods for surface plasmon-coupled directional emission|
|US20050059014 *||Sep 3, 2003||Mar 17, 2005||Michael Pawlak||Analytical platform and detection method with the analytes to be determined in a sample as immobilized specific binding partners|
|US20060054903 *||Sep 16, 2004||Mar 16, 2006||Doktycz Mitchel J||Transparent solid-state structure for diagnostics of fluorescently labeled biomolecules|
|US20060127946 *||Jan 28, 2003||Jun 15, 2006||Montagu Jean I||Reading of fluorescent arrays|
|US20060147147 *||Oct 7, 2002||Jul 6, 2006||Mohammed Zourob||Waveguide structure|
|US20060256331 *||Jul 18, 2006||Nov 16, 2006||University Of Maryland, Baltimore||Optical structures for metal-enhanced sensing|
|US20070015151 *||Sep 24, 2003||Jan 18, 2007||Hopitaux Univesitaires De Geneve||Analytical chip with an array of immobilized specific recognition elements for the determination of clinically relevant bacteria and analytical method based thereon|
|US20070262265 *||May 10, 2006||Nov 15, 2007||Maccraith Brian||Polymer biochip for detecting fluorescence|
|US20080139403 *||Oct 4, 2007||Jun 12, 2008||Horst Vogel||Bioanalytical reagent, method for production thereof, sensor platforms and detection methods based on use of said bioanalytical reagent|
|US20080158559 *||Mar 2, 2006||Jul 3, 2008||Emmanuel Fort||Fluorescence Detection Device|
|US20080161201 *||Mar 5, 2007||Jul 3, 2008||Yokogawa Electric Corporation||Biochip and genetic sequence measuring equipment using the biochip|
|US20080299008 *||Feb 21, 2008||Dec 4, 2008||Eveline Schurmann-Mader||Flow cell array and the utilization thereof for multianalyte determination|
|US20100099100 *||Sep 25, 2009||Apr 22, 2010||Pacific Biosciences Of California, Inc.||'ultra-high multiplex analytical systems and methods"|
|US20100130370 *||Jan 28, 2010||May 27, 2010||Eveline Schurmann-Mader||Flow cell array and the utilization thereof for multianalyte determination|
|US20100135856 *||Jun 10, 2009||Jun 3, 2010||Electronics And Telecommunications Research Institute||Nanoparticle for detecting biomaterials and biosensor by using the nanoparticle|
|US20100227773 *||Mar 17, 2010||Sep 9, 2010||Andreas Peter Abel||Device and method for determining multiple analytes|
|US20100311614 *||Jun 15, 2010||Dec 9, 2010||Avantra Biosciences Corporation||Substrates for Isolating, Reacting and Microscopically Analyzing Materials|
|US20110013375 *||Jul 20, 2010||Jan 20, 2011||Crayola Llc||Illuminated Display Unit|
|US20110222179 *||Mar 10, 2011||Sep 15, 2011||Pacific Biosciences Of California, Inc.||Micromirror arrays having self aligned features|
|CN104593892A *||Jan 25, 2015||May 6, 2015||北京化工大学||Preparation method for nanogold-enhanced fluorescence sheath-core structure nano fiber|
|EP0353937A1 *||Jul 25, 1989||Feb 7, 1990||Applied Research Systems Ars Holding N.V.||Method of assay|
|EP2269724A1||Oct 29, 2005||Jan 5, 2011||Bayer Technology Services GmbH||Method for determining one or more analytes in complex biological samples and use of same|
|WO1990001166A1 *||Jul 25, 1989||Feb 8, 1990||Ares-Serono Research & Development Limited Partnership||Method of assay|
|WO1990006503A2 *||Nov 28, 1989||Jun 14, 1990||Applied Research Systems Ars Holding N.V.||Sensor for optical assay|
|WO1990006503A3 *||Nov 28, 1989||Mar 7, 1991||Ares Serono Res & Dev Ltd||Sensor for optical assay|
|WO2001040778A1||Dec 1, 2000||Jun 7, 2001||Commissariat A L'energie Atomique||Enhancing surface-generated fluorescence signal emitted by a sample|
|WO2002046766A2||Dec 4, 2001||Jun 13, 2002||Ecole Polytechnique Federale De Lausanne||Bioanalytical reagent, method for production thereof, sensor platforms and detection methods based on use of said bioanalytical reagent|
|WO2003023377A1 *||Sep 11, 2002||Mar 20, 2003||Dublin City University||A luminescence-based sensor assembly|
|WO2005003743A2 *||May 20, 2004||Jan 13, 2005||University Of Maryland||Apparatus and methods for surface plasmon-coupled directional emission|
|WO2005003743A3 *||May 20, 2004||Jun 30, 2005||Joseph Lakowicz||Apparatus and methods for surface plasmon-coupled directional emission|
|WO2005031884A1 *||Aug 4, 2004||Apr 7, 2005||The Regents Of The University Of California||Plasmon assisted enhancement of organic optoelectronic devices|
|U.S. Classification||250/483.1, 250/368, 250/487.1|
|Cooperative Classification||G01N21/648, G01N21/643|
|May 10, 1985||AS||Assignment|
Owner name: UNIVERSITY OF ROCHESTER THE ROCHESTER, NY
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNORS:HOLLAND, WILLIAM R.;HALL, DENNIS G.;REEL/FRAME:004405/0836
Effective date: 19850507
|Apr 12, 1990||FPAY||Fee payment|
Year of fee payment: 4
|Apr 18, 1994||FPAY||Fee payment|
Year of fee payment: 8
|Jul 20, 1998||FPAY||Fee payment|
Year of fee payment: 12